Contact rail unit

ABSTRACT

A contact rail unit comprising an elongated body and conductors arranged longitudinally within the body. The conductors are provided with mutually spaced lateral branches and the body is provided with openings for each branch, each opening being displaced in the longitudinal direction of the body with respect to the corresponding branch. The contact fingers of a current collecting devize may be inserted through said openings and brought in contact with said branches by a sliding movement in the longitudinal direction of the body.

U United States Patent 1191 1111 3,778,746

Valtonen Dec. 11, 1973 1 CONTACT RAIL UNIT 3,391,378 7/1968 Fisher 339/22 13 Inventor: Rainer "kka Tapio valtonen, 2,708,264 5/1955 Boyd 339/21 R Soukka Fmland Primary Examiner-Marvin A. Champion [73} Assignee: 0y Nokia Ab, Helsinki, Finland A i t nt Ex i er Robert A, Hafer Filed; Jam 3], 972 Attorney-Enc H. Waters et al.

[21] Appl. No.: 221,929 [57] ABSTRACT A contact rail unit comprising an elongated body and [30] For i A li ti P i it D t conductors arranged longitudinally within the body.

- The conductors are provided with mutually spaced lat- Feb. l97l Fmland ..28l /7l e a] a c es and he b y is provided with p g [52] U.S. Cl 339/21 R for each branch each opening being displaced in mg iff d 'f'g longitudinal direction of the body with respect to the 1e 0 care correspondmg branch. The contact fmgers of a cur- 339/21 21 22 22 22 24 rent collecting devize may be inserted through said openings and brought in contact with said branches by [56] References C'ted a sliding movement in the longitudinal direction of the UNITED STATES PATENTS b 2,313,452 3/1943 OBrien 339/23 3,059,204 10/1962 Johnson 339/14 12 Clams 6 guns 4 3 /.l L h /11 l 5 1| ll l I I L 1 I l 1. 3 7 6 FIG.

PATENTH] DEC] 1 I975 CONTACT RAIL UNIT Previously, various contact rail systems are known for the current collecting of lamps, electrical apparatus and equivalent which systems are based on the use of a closed box-like body rail which is at certain distances fitted with contact sockets connected to each other by means of ordinary insulated electric conductors running inside the closed body rail. The necessity of special contact sockets and the connecting of the sockets to the electric conductors, however, make such current rails complicated and expensive.

Also, contact rails are known that are based on the use of a channel-like current rail which is at one side continuously open and which accommodates a number of uninsulated conductors fastened to the rail longitudinally. Such a current rail, as a matter of fact, provides an almost unlimited possibility of moving the lamps from one place to another, but the open construction of the current rail, however, imposes of security reasons certaim restrictions to the installation position of such rails. Although it is not possible to get accidentally an electric stroke from such a current rail by just inserting the fingers into the rail, it is, however, at least theoretically possible that for example when wiping of the dust by means of damp cloth, the cloth may come into contact with current supplying conductors. Therefore a certaim minimum installation height is required for such open current rails, for example in Finland 230 cm.

A purpose of the present invention is to eliminate the above disadvantages and to produce a contact rail unit which provides the advantages of contact rails of the latter type in respect of simplicity of construction and of almost unlimited possibilities of current collecting and which is nevertheless not burdened by the above restriction of installation.

This purpose is according to the invention obtained by means of a contact rail unit that is characterized in that the conductors are provided with mutually spaced branches extending transversally in respect to the longitudinal direction of the conductor and that openings corresponding to said branches are formed into the body for the insertion of said contact fingers.

According to the invention, a contact rail system is obtained in which the current rail consisting of the body and the conductors is completely closed with the exception of several mutually spaced openings for the contact fingers of the current collecting device. In this case said openings can be made so small that unintentional insertion of foreign objects into the openings is almost impossible. The conductor branches are moreover located well protected inside the body alongside the corresponding openings. In this way the current rail can be made even better touch-protected than an ordinary box-like contact rail. Thus, the contact rail system is burdened by no restrictions of installation.

Due to the branches of the conductors, all the openings of the body can be made to lie along the same longitudinal line, for which reason the current rail may be made very narrow and small. Due to the branches, the conductors are also longitudinally locked into the body, and the branches allow for a certain heat elongation of the conductors. The flexible construction of the conductors and the flat shape of the body also enable the entire unit to be wound into a coil, which is a considerable production-technical advantage and simplifies the installation.

The invention will be described more in detail in the following under reference to the attached drawing, in which FIG. 1 shows a perspective view of a favourable embodiment of a contact rail unit,

FIG. 2 shows the interior of the unit,

FIG. 3 shows a perspective view of a current collecting device intended for the unit,

FIGS. 4 and 5 show the current collecting device as viewed from the top and from the side, respectively, and

FIG. 6 shows a cross-section view of the unit as arranged into a support rail.

The contact rail unit 1 shown in FIGS. 1 and 2 consists of an elongated channel-like body 2 of insulating material. Longitudinal grooves 3 have been formed for uninsulated conductors 4 inside the flanges of the body.

The conductors 4 have been formed with mutually spaced curves 5 that extend perpendicularly from the conductor into the interior of the body through openings 6 in the grooves 3 and are pressed against the bottom 2a of the body 2. In the bottom of the body, alongside each curve, a through hole 7 has been formed. The openings have been located along the same line in the longitudinal direction of the body.

As appears from FIGS. 1 and 2, the curves and openings are located as groups so that each group includes one curve 5 of each conductor 4 and the corresponding openings 7.

An embodiment of a current collecting device intended for the unit according to FIGS. 1 and 2 is shown in FIGS. 3 to 5. The current collecting device 8 includes a body 9 of an insulating material, contact fingers 10 which are fastened to the body and provided with wire terminals, an intermediate plate 11, and a spring 12 which presses the intermediate plate outwards from the body. The distance between the contact fingers 10 corresponds to the distance of the openings 7 of each group of openings.

The current collecting device is brought into contact with the conductors 4 in such'a way that the contact fingers are first inserted through the openings 7 of the unit and then pushed in the longitudinal direction of the unit. I-Iereby the L-shaped ends of the contact fingers slide into the conductor curves 5. Due to the flexible intermediate plate 11 the contact fingers are reliably pressed into contact with the curves.

The ends of the contact fingers of the current collecting device have been formed of different sizes (FIG. 4) and the openings 7 of the unit 1 have been formed of corresponding sizes (FIG. 1) so that the current collecting device can be inserted into the unit 1 only in a certaim position.

In accordance with FIG. 6, the unit 1 has been inserted into a separate metallic support rail 13, which gives the unit mechanical rigidity. If desired, the unit 1 may be accommodated in the upper casing 13a of the support rail, whereby the lower casing of the support rail can be used as fastening space for example for the holder of a lamp and the current collecting device can be invisibly inserted into the support rail.

The drawing and the connected specification are only intended to illustrate the idea of the invention. In its details the contact rail unit according to the invention may vary considerably within the scope of the claims. Thus, the unit may, instead of two conductors, be fitted with e.g. four conductors, in which case two conductors are arranged inside each flange of the body and the curves of the lower conductor pair and those of the upper conductor pair are located at different levels parallel with the bottom of the body. Moreover, the body may be closed by means of a cover 14 (FIG. 6) which has been provided with an earthing conductor 15. lnstead of the curves the conductors 4 may be provided with mutually spaced separate pins which are welded to the conductors to protrude laterally from said conductors.

What I claim is:

1. In combination, a contact rail assembly comprising an elongate body; a pair of transversely spaced longitudinally extending conductors being positioned along a bottom surface of said body, said conductors each including mutually spaced transversely extending branches; apertures formed in said body adjacent each said branch and longitudinally offset therefrom in predetermined, spaced relationship, along the axis of said body, said conductor branches engaged by the contact fingers of a current collecting device as contact fingers are inserted through said apertures and moved longitudinally along said elongate body into superimposed relationship with said conductor branches.

2. A contact rail unit according to claim 1, characterized in that the conductors 4 are bent into laterally extending curves 5 forming said branches.

3. A contact rail unit according to claim 1, characterized in that the body 2 has a channel-shaped section, whereby the conductors 4 are arranged inside the two flanges of the body and the conductor branches 5 are positioned against the bottom 2a of the body.

4. A contact rail unit according to claim 3, characterized in that the inner space ofthe channel-section body 2 is closed by a cover plate 14.

5. A contact rail unit according to claim 4, characterized in that the cover plate 14 is fitted with an earthing conductor 15.

6. A contact rail unit according to claim 1, characterized in that the body 2 is shaped to be fastened to sup port rail 13.

7. A contact rail unit according to claim 1, character ized in that the branches 5 of the conductors 4 are ar' ranged in mutually spaced groups so that each group includes one branch 5 of each conductor 4.

8. A contact rail unit according to claim 1, characterized in that the openings 7 for different conductors 4 in the body 2 are of different sizes or shapes.

9. A contact rail unit according to claim 1, characterized in that the openings 7 of the body 2 are arranged substantially aligned in the longitudinal direction of the body.

10. A current collecting device for a contact rail unit according to claim 1, which current collecting device comprises a body 9 and at least two projecting contact fingers 10 fastened to the body, characterized in that the contact fingers 10 are fastened to the body 9 in predetermined spaced relationship, each said contact finger adapted to be inserted through a respective aperture in the contact rail unit 1 so as to contact with the branches 5 of the corresponding conductors 4 upon longitudinal move in the direction thereof.

11. A current collecting device according to ciaim 10, characterized in that the contact fingers 10 are bent to form Lshaped flexible ends adapted to slidingly engage the branches 5 of the corresponding conductors 4 when the collecting device body 9 is moved in the longitudinal direction of the contact rail unit 1.

12. A current collecting device according to claim 10, characterized in that the contact fingers 10 are substantially longitudinally aligned. 

1. In combination, a contact rail assembly comprising an elongate body; a pair of transversely spaced longitudinally extending conductors being positioned along a bottom surface of said body, said conductors each including mutually spaced transversely extending branches; apertures formed in said body adjacent each said branch and longitudinally offset therefrom in predetermined, spaced relationship, along the axis of said body, said conductor branches engaged by the contact fingers of a current collecting device as contact fingers are inserted through said apertures and moved longitudinally along said elongate body into superimposed relationship with said conductor branches.
 2. A contact rail unit according to claim 1, characterized in that the conductors 4 are bent into laterally extending curves 5 forming said branches.
 3. A contact rail unit according to claim 1, characterized in that the body 2 has a channel-shaped section, whereby the conductors 4 are arranged inside the two flanges of the body and the conductor branches 5 are positioned against the bottom 2a of the body.
 4. A contact rail unit according to claim 3, characterized in that the inner space of the channel-section body 2 is closed by a cover plate
 14. 5. A contact rail unit according to claim 4, characterized in that the cover plate 14 is fitted with an earthing conductor
 15. 6. A contact rail unit according to claim 1, characterized in that the body 2 is shaped to be fastened to support rail
 13. 7. A contact rail unit according to claim 1, characterized in that the branches 5 of the conductors 4 are arranged in mutually spaced groups so that each group includes one branch 5 of each conductor
 4. 8. A contact rail unit according to claim 1, characterized in that the openings 7 for different conductors 4 in the body 2 are of different sizes or shapes.
 9. A contact rail unit according to claim 1, characterized in that the openings 7 of the body 2 are arranged substantially aligned in the longitudinal direction of the body.
 10. A current collecting device for a contact rail unit according to claim 1, which current collecting device comprises a body 9 and at least two projecting contact fingers 10 fastened to the body, characterized in that the contact fingers 10 are fastened to the body 9 in predetermined spaced relationship, each said contact finger adapted to be inserted through a respective aperture in the contact rail unit 1 so as to contact with the branches 5 of the corresponding conductors 4 upon longitudinal move in the direction thereof.
 11. A current collecting device according to claim 10, characterized in that the contact fingers 10 are bent to form L-shaped flexible ends adapted to slidingly engage the branches 5 of the corresponding conductors 4 when the collecting device body 9 is moved in the longitudinal direction of the contact rail unit
 12. A current collecting device according to claim 10, characterized in that the contact fingers 10 are substantially longitudinally aligned. 